Transient reduction of mutans streptococci on tooth surfaces using a chlorhexidine-containing glass ionomer cement varnish

Chlorhexidine (CIM) has been incorporated in polymer-based varnishes to red uce mutans streptococci (ms) by the sustained release of CHX. Such varnishe s often adhere well to teeth initially but are easily peeled off. To be eff ective, repeated application is necessary. Glass ionomer (GI) cements inter acts with tooth minerals to form a stronger bond, and the inherent brittlen ess of the cement makes it difficult to remove in large fragments. The fluo ride content may also reduce demineralisation. The aim of this study was to observe whether ms could be reduced interproximally and in saliva by a sin gle application of a GI cement containing 3.3% CHX gluconate (CHX-GI). Afte r professional tooth cleaning and a mouth rinse for 2 min with 0.2% CHX, th e teeth of six subjects were coated with CHX-GI cement. An additional six s ubjects were treated with a GI cement that did not contain CHX, and seven s ubjects received professional tooth cleaning only. Ms samples were taken in terproximally with the tooth pick method before and after treatment. Interp roximal levels were classified according to the number of colony-forming un its (c.f.u.) found: 0, 1-20, 21-100, and >100. Saliva ms were sampled with the Strip Mutans method. After four weeks, the interproximal levels of ms h ad decreased only in the CHX-GI group (p<0.05). In this group 9 of 14 highl y colonised sites (>100 c.f.u.) remained reduced throughout this period. In the GI and the untreated group a slight increase of ms interproximally was seen after one week. The interproximal ms scores in all groups approached baseline levels after 8 weeks. There were no significant differences in sal iva ms levels between the groups during the test period. GI cement may be a possible vehicle for CHX in reducing ms interproximally.